通过赋值运算符分配对象的引用
Assign reference of object by assignment operator
我对下面的程序有疑问。在控制器中,saveContact 函数:如果我将行 ContactService.save($scope.newcontact);
更改为 $scope.contacts.push($scope.newcontact);
看来程序是一样的。我想知道原因是否是当这一行 ($scope.contacts = ContactService.list();
被执行时,服务中联系人列表的引用被分配给 $scope.contacts
以便将新联系人推送到 $scope.contacts
是相同的将新联系人推送到服务中的联系人列表?
<div ng-app="app" ng-controller="ContactController">
<form class="well">
<label>Name</label>
<input type="text" name="name" ng-model="newcontact.name" />
<label>Email</label>
<input type="text" name="email" ng-model="newcontact.email" />
<label>Phone</label>
<input type="text" name="phone" ng-model="newcontact.phone" />
<br/>
<input type="hidden" ng-model="newcontact.id" />
<input type="button" value="Save" ng-click="saveContact()" class="btn btn-primary" />
</form>
<table class="table table-striped table-bordered">
<thead>
<tr>
<th>Name</th>
<th>Email</th>
<th>Phone</th>
<th>Action</th>
</tr>
</thead>
<tbody>
<tr ng-repeat="contact in contacts">
<td>{{ contact.name }}</td>
<td>{{ contact.email }}</td>
<td>{{ contact.phone }}</td>
<td> <a href="javascript:void(0)" ng-click="edit(contact.id)">edit</a> | <a href="javascript:void(0)" ng-click="delete(contact.id)">delete</a>
</td>
</tr>
</tbody>
</table>
</div>
var module = angular.module('app', []);
module.service('ContactService', function () {
//to create unique contact id
var uid = 1;
//contacts array to hold list of all contacts
var contacts = [{
id: 0,
'name': 'Viral',
'email': 'hello@gmail.com',
'phone': '123-2343-44'
}];
//save method create a new contact if not already exists
//else update the existing object
this.save = function (contact) {
if (contact.id == null) {
//if this is new contact, add it in contacts array
contact.id = uid++;
contacts.push(contact);
} else {
//for existing contact, find this contact using id
//and update it.
for (i in contacts) {
if (contacts[i].id == contact.id) {
contacts[i] = contact;
}
}
}
}
//simply search contacts list for given id
//and returns the contact object if found
this.get = function (id) {
for (i in contacts) {
if (contacts[i].id == id) {
return contacts[i];
}
}
}
//iterate through contacts list and delete
//contact if found
this.delete = function (id) {
for (i in contacts) {
if (contacts[i].id == id) {
contacts.splice(i, 1);
}
}
}
//simply returns the contacts list
this.list = function () {
return contacts;
}
});
module.controller('ContactController', function ($scope, ContactService) {
$scope.contacts = ContactService.list();
$scope.saveContact = function () {
//ContactService.save($scope.newcontact);
$scope.contacts.push($scope.newcontact); ----change here
$scope.newcontact = {};
}
$scope.delete = function (id) {
ContactService.delete(id);
if ($scope.newcontact.id == id) $scope.newcontact = {};
}
$scope.edit = function (id) {
$scope.newcontact = angular.copy(ContactService.get(id));
}
})
Link 到 the original program.
不太一样。 $scope.contacts
指向的数组和ContactsService
内部使用的数组是同一个数组,但是ContactsService
在[=13=中工作] 你 而不是 直接推到 $scope.contacts
。
具体来说,如果您要添加的联系人是 新 联系人(没有 ID),那么它会为其添加一个 ID。此外,save
将更新现有联系人。
您的更改似乎有效,因为您正在将联系人添加到 ContactsService
内部数组,但您绕过了 ContactsService
指定的 API。
您的方法最终可能会复制 列表中的联系人以及不加区别地添加它们。
我对下面的程序有疑问。在控制器中,saveContact 函数:如果我将行 ContactService.save($scope.newcontact);
更改为 $scope.contacts.push($scope.newcontact);
看来程序是一样的。我想知道原因是否是当这一行 ($scope.contacts = ContactService.list();
被执行时,服务中联系人列表的引用被分配给 $scope.contacts
以便将新联系人推送到 $scope.contacts
是相同的将新联系人推送到服务中的联系人列表?
<div ng-app="app" ng-controller="ContactController">
<form class="well">
<label>Name</label>
<input type="text" name="name" ng-model="newcontact.name" />
<label>Email</label>
<input type="text" name="email" ng-model="newcontact.email" />
<label>Phone</label>
<input type="text" name="phone" ng-model="newcontact.phone" />
<br/>
<input type="hidden" ng-model="newcontact.id" />
<input type="button" value="Save" ng-click="saveContact()" class="btn btn-primary" />
</form>
<table class="table table-striped table-bordered">
<thead>
<tr>
<th>Name</th>
<th>Email</th>
<th>Phone</th>
<th>Action</th>
</tr>
</thead>
<tbody>
<tr ng-repeat="contact in contacts">
<td>{{ contact.name }}</td>
<td>{{ contact.email }}</td>
<td>{{ contact.phone }}</td>
<td> <a href="javascript:void(0)" ng-click="edit(contact.id)">edit</a> | <a href="javascript:void(0)" ng-click="delete(contact.id)">delete</a>
</td>
</tr>
</tbody>
</table>
</div>
var module = angular.module('app', []);
module.service('ContactService', function () {
//to create unique contact id
var uid = 1;
//contacts array to hold list of all contacts
var contacts = [{
id: 0,
'name': 'Viral',
'email': 'hello@gmail.com',
'phone': '123-2343-44'
}];
//save method create a new contact if not already exists
//else update the existing object
this.save = function (contact) {
if (contact.id == null) {
//if this is new contact, add it in contacts array
contact.id = uid++;
contacts.push(contact);
} else {
//for existing contact, find this contact using id
//and update it.
for (i in contacts) {
if (contacts[i].id == contact.id) {
contacts[i] = contact;
}
}
}
}
//simply search contacts list for given id
//and returns the contact object if found
this.get = function (id) {
for (i in contacts) {
if (contacts[i].id == id) {
return contacts[i];
}
}
}
//iterate through contacts list and delete
//contact if found
this.delete = function (id) {
for (i in contacts) {
if (contacts[i].id == id) {
contacts.splice(i, 1);
}
}
}
//simply returns the contacts list
this.list = function () {
return contacts;
}
});
module.controller('ContactController', function ($scope, ContactService) {
$scope.contacts = ContactService.list();
$scope.saveContact = function () {
//ContactService.save($scope.newcontact);
$scope.contacts.push($scope.newcontact); ----change here
$scope.newcontact = {};
}
$scope.delete = function (id) {
ContactService.delete(id);
if ($scope.newcontact.id == id) $scope.newcontact = {};
}
$scope.edit = function (id) {
$scope.newcontact = angular.copy(ContactService.get(id));
}
})
Link 到 the original program.
不太一样。 $scope.contacts
指向的数组和ContactsService
内部使用的数组是同一个数组,但是ContactsService
在[=13=中工作] 你 而不是 直接推到 $scope.contacts
。
具体来说,如果您要添加的联系人是 新 联系人(没有 ID),那么它会为其添加一个 ID。此外,save
将更新现有联系人。
您的更改似乎有效,因为您正在将联系人添加到 ContactsService
内部数组,但您绕过了 ContactsService
指定的 API。
您的方法最终可能会复制 列表中的联系人以及不加区别地添加它们。